Hi Alisa,
The best way to understand OSC in IanniX is to open the Help window (button in the toolbar) and to for example, move a trigger in the GUI. At the bottom of the Help window, you’ll see the OSC message to send to reproduce the action (if you see setPos t x y z, then the OSC syntax is /iannix/setPos t x y z). You can also copy a small Max patch from this help window.
Good luck!